Franco-Prussian War

What happened

Prussian Chancellor Bismarck maneuvered French Emperor Napoleon III into declaring war (July 1870). Prussian military organization and railways proved superior. Key victories: Sedan (Sept 1870), where Napoleon III was captured. France collapsed militarily; a republican government continued fighting from Paris. Prussia's General von Moltke's systematic strategy outmatched French improvisation. Germans surrounded Paris; siege starvation forced French surrender (May 1871). Germany unified under King Wilhelm I; France lost Alsace-Lorraine and paid a crushing indemnity (5 billion francs). Roughly 139,000 soldiers died; 100,000 civilians died in Paris siege.

Why it mattered

Prussia's victory unified Germany and displaced France as Western Europe's dominant power. The shift terrified Europe and led to alliance-building that culminated in WWI. Germany's annexation of Alsace-Lorraine created a revanchist French memory that motivated French alliance-seeking. The war demonstrated Prussian military superiority and German unification's consequences. It accelerated European arms races and militarization. Modern France's strategic obsession with Germany, even during 1945-1990 Cold War, partly stems from 1870. The war inaugurated the modern era of industrial warfare and nationalist fervor.